NPL & NGI compose a good practice guide for graphene metrology

The National Graphene Institute at the University of Manchester has joined forces with the NPL to develop a guide, as part of NPL's good practice guide series, that conveys "a detailed description of how to determine the key structural properties of graphene, so that the graphene community can adopt a common metrological approach that allows the comparison of commercially available graphene materials. This guide brings together the accepted metrology in this area".

The guide, titled Characterization of the Structure of Graphene, follows last month's release of the NPL's work on the first ISO (International Organization for Standardization) graphene standard. It describes the high-accuracy and precision required for verification of material properties and enables the development of other faster quality control techniques in the future. The guide is intended to form a bedrock for future interlaboratory comparisons and international standards.

Using this guide, users with previous characterization expertise within industry can more reliably, quantitatively and comparably measure the structural properties of commercially supplied graphene. The guide can be used to measure the properties of both CVD-grown graphene and samples containing graphene flakes, determining the substrate coverage, percentage of single layer graphene, level of disorder and layer alignment for the former, as well as the lateral flake size range and corresponding thickness along with the level of disorder for the latter.

It is hoped that graphene's commercial adoption will be enhanced by answering the two vital questions concentrating on the characteristics of commercially-supplied graphene and the best ways to make use of them. The launch of common industrial metrics, regarding for instance the number of layers or flake size, is important for the uptake of graphene-based technologies.